According to BKIS, soma students in Hai Phong, Can Tho City, and HCM City created and uploaded these viruses. There were six variants of the viruses, two each of KkcYM, FunniYM and HpBotYM, which spread through Yahoo Messenger.

The Funni virus comes with a download link. As soon as a user clicks on the link it downloads funni.exe that gets installed on the PC and then spreads the virus. The Funni virus behaves in the same way as its other two brother viruses. When the exe file is installed the viruses take control of the address list in the user's Yahoo Messenger. It then uses these addresses to send the virus 'download link' to infect their computers too.

The Funni virus exists on a website. When users visit this site, the virus immediately affects their PCs. The website link has accompanying messages, which tempt people to open them hereby result in spreading the virus further.

The Funni virus is relatively less dangerous to the PCs. But it has the ability to send commands to the Yahoo Messenger software on the targeted PC. It sends the website link to all the addresses in the people's list of the affected PC. The virus poses another problem that is it installs keylogger program onto the infected PC. This enables the attacker to read the keystrokes of a keyboard on the targeted computer and then access sensitive information of the user like password and credit card number. BKIS has already confirmed more than thousand cases of online password theft in Vietnam.

BKIS website has an anti-Funni software that can be downloaded. If a PC has its Yahoo Messenger affected, users are recommended to use third party clients such as "Gaim". This is freely available on the Internet and can be used till the virus is removed. Besides, for overall safety of their PCs users should deploy proper anti-virus software along with regular updating.